1. Field of the lnvention
This invention relates to an optical lens for a human eye or mammalian eye (hereinafter included in the term "eye" as used herein), which comprises a transparent lens body which is adapted to be placed onto, into or implanted within the eye to obtain an optical effect by increasing the normal depth of focus of the eye in order to substitute for the Ioss of at least one of the focusing power and the accommodation of the eye and, more particularly, relates to an optical lens having a transparent lens body wherein the transparent lens body has formed in the central area thereof at least one stenopaeic opening to seIectlveIy intercept and pass light throu8h the Iens body aIon the visual axis of the eye onto the fovea centralis of the eye to obtain the desired optical effect by increasing the normal depth of focus of the eye in order to substitute for the loss of at least one of the focusing power and the accommodation of the eye.
2. Description of the Prior Art
It is well known in the art to utilize an intraocular lens, a corneal overlay, contact lens or other special lens which can be implanted into the eye to obtain an optical effect for the eye as a substitution of the loss of both the focusing power or the accommodation of the eye.
It is well known to persons skilled in the art to test the visual acuitY of a patient by using a multiple pinhole testing device. The multiple pinhole testing device which is used for testing the eye is in the form of a dark or nontransparent member having a "pinhole" formed in the center thereof and a plurality of "pinholes" spaced radially about the center "pinhole." One typical multiple pinhole testing device has a single center "pinhole," a first ring comprising eight multiple "pinholes" arranged equi-distantly and equi-angular around the center "pinhole" and a second ring of eight multiple "pinholes" formed with a larger radius and spaced at equal distance from and positioned at equal angles around the central stenopaeic opening. By use of the multiple pinhole testing device, an ophthalmologist can quickly test a patient to see if the patient's vision can be corrected by use of a lens compared to the visual loss due to the eye heing diseased. An example of using such a multiple pinhole testing device is as follows: Assume that a hypothetical patient has a vision of 20/60. The patient looks through a hole of the multiple pinhole testing device. If the eye can be optically corrected, the patient would obtain or experience 20/20 vision by viewing an object through any one of the pinholes in the multiple pinhole testing device. However, if the patient's vision is not improved, that is, still remains 20/60 when viewing through the pinhole, then the ophthalmologist may conclude that the eye has a disease affecting the vision.
lt is also well known in the art to utilize what is referred to as a "pinhole camera," that is, a camera which has no lens. TYpicallY, such a camera consists of a darkened box with a small hole on one side, so that an image of an outside ob]ect is projected on the opposite side inside the box where it is recorded on photographic film.
It is also known in the art to have intraocular lenses which have positioning holes formed therethrough. Typical of such intraocular lens is a lens offered for sale and sold by Iolab Corporation referred to as the Model 103J Posterior Chamber Lens. One example of such a lens, is a lens having a 13 mm. haptic diameter, 6 mm. optic diameter, two positioning holes 180.degree. apart and located parallel to the plano surface. In the Iolab Corporation Model 103J Posterior Chamber Lens, the positioning holes are located on the edge of or peripherally on the lens body and are utilized by an ophthalmologist for positioning the lens within the eye, and not for the purpose of providing an optical effect.
It is also known in the art that contact lens have very small, porous openings to pass metabolic gases such as oxygen or carbon dioxide to prevent swelling or loss of clarity of the cornea.
lt is also known in the art to utilize a contact lens which can be characterized as a mu1ti-focal length contact lens. Typical of such lens are those disclosed in U.S. Pat. No. 3,270,099 and 3,034,403. U.S. Pat. No. 3,270,099 discloses a lens which has a central portion of one optical power formed of one material and a peripheral portion of a different optical power surrounding the central portion. The central and peripheral portions are arranged so that their optical axes coincide and the central portion has a select dimension. U.S. Pat. No. 3,270,099 discloses that the central portion is either formed to be on the surface of the lens bodY or implanted within the lens body to obtain the desired optical effect.
U.S. Pat. No. 3,034,403 discloses a lens which may be formed of a black or dark absorption area occupying the entire thickness of the central area of the lens and having a small plug of a clear or lighter area to fabricate a "pinhole" type of contact lens. ln the structure of a contact lens formed of U.S. Pat. No. 3,034,403, the lens body which is formed of two different materials, the center of which is transparent and the outer peripheral area of which is dark or black.
U.S. Pat. No. 4,010,496 discloses a bifocal lens which is adapted to be implanted into the anterior chamber of the eye having an air space in the upper lens edge to position the lens at the upper edge of the pupil in a dilated and constricted state. The air space is utilized for positioning on the lens, and is not intended to nor does it provide any optical effect.
U.S. Pat. No. 4,485,499 discloses an intraocular posterior chamber lens having two spaced elongated ridges which are located on the back surface of the lens so as to contact the posterior capsule and to keep the posterior capsule away from the hack side of the lens. In the event of haziness or opacification of the posterior capsule, the open zona formed by the ridges between the rear of the lens and the posterior capsule allows corrective or restorative openings to be made in the posterior capsule. The so provided ridges do not have any optical correction effect.
A recent study disclosed in an article encaptioned HOLES IN CLEAR LENS DEMONSTRATE A PINHOLE EFFECT by Peter Zacharia, David Miller, M.D. appeared in the Apr., 1988, issue of ARCHIVES 0F OPHTHALMOLOGY, Volume 106, Pages 511-513, (referred to herein as the "Zacharia-Miller Reference") describes a new variant of the pinhole testing principle utilizing holes drilled in clear plastic lenses. A study discloses that holes drilled in a clear plastic lens held in combination with a blurring lens can overcome the blurring effect as much as a traditional pinhole. Specifically, the study disclosed that holes of a different diameter placed in lenses of different spherical power can improve visual acuity that had been degraded by a series of blurred spherical lenses. The study concluded that, in general, a hole in a clear lens improves visual acuity for progressively stronger blurring lenses. The study disclosed that the material utilized for the lens was a clear plastic lens, and the clear plastic lens was positioned by the lens relative to a patient s eye so that the patient can view the target, which in this case was Snellen-type E target at 75-foot-candle illumination, through the small hole drilled in the plastic lens. In front of the plastic lens having the hole there was placed a spherical convex blurring lens that degraded the image. The visual acuity improvement (VAI) was defined as follows: VAI=(visual acuity through pinhole and clear lens and blurring lens).times.0.1/visual acuity through blurring lens alone. This study did not suggest, disclose or teach using a transparent lens body having a "pinhole" formed therethrough as a means for selectively intercepting and passing light through a lens body onto the retina or the fovea centralis in a manner to obtain an optical effect by increasing the normal depth of focus of the eye in order to substitute for the loss of at least one of the focusing power and the accommodation of the eye.